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22 December 2008

BEWARE!

MOBILE PHONE COULD EXPLODE UNDER EXTREME HOT ENVIRONMENT!

SOME LESSONS ARE BEST

LEARNED BY EXPERIENCE!
An incident of a mobile phone
explosion inside a vehicle cabin was
reported in Saudi Arabia lately.
Incident Background
Mobile phone units were left inside the
car compartment while the vehicle was
parked in an open area. One of the
phones had its power “on”. It was close
to midday. Reportedly after an hour in
the park, one of the mobile phones
exploded.

What Went Wrong?
Obviously the mobile phone’s battery is
the only component as the legitimate
source of stored energy.
The solar heat obviously pressurized
the car’s closed cabin. What triggers
the explosion could be the overheated
battery caused by extremely high
temperature magnified by the
windshield (glass) and the sealed
(unventilated) vehicle cabin.

Lessons Learned
Better not to leave mobile phones in
car compartment especially when the
vehicle is exposed to direct sunlight for
a prolonged period.



Figure 1&2: Shattered car windshield as a result of the
explosion







Figure 3: Effects of the explosion



Figure 4: Remains of phone gadget



Figure 5: Evidence of rupture and heavy melting due to intense temperature as a consequence of the explosion


Figure 6: Car compartment damages and mobile phone
units were destroyed beyond repair.


01 December 2008

MY JOBS

SERVICE DISH


SERVER CHECK


CHEKING FOR LINK NETWORK

Setting Up a Windows Network

Installing a NIC
  • Physical installation
    -PCI or ISA card
    -PC Card (PCMCIA)
    -USB
  • Setup in Windows
    -Run Setup utility to install driver
    -Configure any options as needed
    -Test to confirm functionality


Installing a Hub, Switch, or AP

  • Connect network cables
  • Connect AC power to device
  • Start up PC(s) and test network connectivity


Networking Software and the OSI Model



Version Differences in Windows Networking
  • Windows 95, 98, Me
    -Single set of properties for all networking as a whole
  • Windows 2000, XP
    -Each network connection has its own properties
    -Each network connection can have different protocols and services
Windows 2000/XP Networking
  • Choose a network connection and then view its Properties


Network Client Software
  • Client for Microsoft Networks
    -Might already be installed
    -Installed during Windows Setup if a NIC is detected
    -Installed when you run Network Setup Wizard

  • Client for Netware Networks
    -Must be manually installed
    -Not available in all versions

Manually Installing Network Client Software

  • Windows 9x/Me
    -Add client from Networks dialog box

  • Windows 2000/XP
    -Choose a network connection and add client for that connection




Protocols
  • TCP/IP
    -Usually installed by default
    -Required for Internet
    -Used by most networks

  • NetBEUI
    -Older, compact protocol
    -Not routable
    -Not available in Windows XP

  • IPX/SPX-Compatible
    -Internetwork Packet Exchange/Sequenced Packet Exchange
    -Required for Client for Netware Networks
Binding Protocols
  • Required in Windows 9x/Me because of the single set of Network settings
  • Associates a protocol with a client or NIC
Binding Protocols





Checking for Network Connectivity
  • Browse My Network Places (or Network Neighborhood)



Changing the Computer Name and Workgroup Name
  • In System Properties:
    -Windows 2000: Network Identification tab
    -Windows XP: Computer Name tab in System properties




Network Setup with Wizards
  • Windows Me:
    -Home Networking Wizard
  • Windows XP:
    -Network Setup Wizard
Understanding TCP/IP
  • IP Addresses
    -32-bit binary number
    -Broken down into four 8-digit binary numbers
    -Each binary number converted to decimal
    -Example: 1100111.10010110.11000000.00001100(equivalent to 207.150.192.12)

Assigning IP Addresses

  • Static: Fixed address, assigned to each PC
  • Dynamic: Address assigned to the PC by a DHCP server

  • Automatic Private IP Address (APIPA): Address assigned by default if DHCP server is not available
Subnet Masks
  • Tells where the network address divides from the host address


  • Binary versions always have the 1s first, followed by the 0s
    -Example, 11111111.11111111.11111111.00000000
    -When converted to decimal:255.255.255.0
DNS Server
  • Stands for Domain Name System
  • Translates between URLs and IP addresses on the Internet

  • Many DNS servers on the Internet, all sharing data with one another
Checking PC’s IP Address
  • Windows 2000 or XP:
    1.Display properties for desired connectionDisplay properties for TCP/IP

Working with the BIOS Setup Program

BIOS
  • Basic Input Output System
  • Motherboard has a BIOS

  • Other devices may also have a BIOS (ex. printer, network router, video card)

  • Typically stored on a ROM or Flash RAM chip
CMOS
  • Complementary Metal Oxide Semiconductor
  • Type of RAM used for storing exceptions to BIOS settings
  • Powered by motherboard battery full-time


Accessing BIOS Setup


  • Watch for a message at startup telling which key to press




BIOS Setup Utility




Exiting BIOS Setup
  • Refer to message onscreen for instructions

  • F10 is typical for saving changes
  • Esc is typical for discarding changes



Floppy Drive Configuration
  • BIOS does not typically detect floppy drives



Hard Drive Configuration
  • Usually Plug-and-Play, but manual setup is possible; refer to label on disk drive


Boot Configuration

  • Set boot order (CD, Hard, Floppy, etc.)




Plug and Play
  • When Plug and Play OS is assumed, BIOS relinquishes control of many hardware resources

  • Reset Configuration resets BIOS assignments of resources from its own Plug and Play

  • Assign IRQ for USB support enables USB devices to work before OS loads

Integrated Peripherals

  • Legacy parallel and serial ports

  • Set addresses or enable/disable




Power Management
  • Can be configured in BIOS or in OS

  • OS is preferable if possible

  • Power management turned on in both places can result in conflict

Recover from Bad BIOS Changes

1.Find reset jumper on motherboard
2.Change its position
3.Power system on for 5 to 10 seconds
4.Power system off
5.Reset jumper

Install BIOS Updates

  • Download update from manufacturer’s Web site

  • Check instructions on Web site

  • Many types of updaters
    *Command line utilities
    *Windows-based utilities
    *Boot disks

Replace BIOS Chip

  • Pull chip with chip puller tool

Video Card Concepts & Troubleshooting

Video Card Concepts
  • Acts as a hardware interface between monitor and PC

  • Has its own chipset and RAM, like a motherboard

  • Talks to the OS via a driver
Video Card Concepts


Video Card Concepts

Video Resolution
  • Pixels: Individual dots in a particular display resolution
  • Examples:
    640x480
    800x600
    1024x768

Monitor Resolution
  • Triad: One set of one red, one green, one blue phosphor

  • Number of triads per pixel depends on display resolution chosen in OS


Video Card Types

  • PCI Express:
    *New type of motherboard slot in 2004
    *Faster than AGP

  • AGP:
    *AGP slot on motherboard designed specifically for video card
    *Fast interface

Video Card Types





Video Chipset
  • Not always the same brand as the video card itself

  • Determines overall driver class compatibility




Video RAM

  • How Much RAM needed for a particular resolution?
    *Horizontal resolution x vertical resolution x color depth in bits
    *Convert answer to bytes by dividing by 8
    *Example: 1024 x 768, 24-bit color
    *Number of pixels: 1024 x 768 = 786,432
    *Bits required: 786,432 x 24 = 18,874,368
    *Convert to bytes: 18,874,368 ÷ 8 = 2,359,296

3D Acceleration

  • Increases amount of RAM required by about 4X because extra RAM is needed for buffers


Install a Video Card

1.Remove old video card if needed
2.Remove backplate from slot if needed
3.Insert video card firmly in slot
4.Secure it with screw or retainer bar
5.Connect a monitor, and boot




Set Display Properties in Windows


1.Install correct driver for video card if needed
2.Right-click the desktop, choose Properties
3.Change resolution and color depth on Settings tab



Troubleshooting Video Card

  • Nothing appears on-screen
    *Monitor turned off
    *Monitor contrast turned down
    *Monitor not connected
    *PC not powered on
    *Defective video card
    *Not installed correctly
  • Screen has a red, blue, or green tint
    *Pin broken on monitor or video card connector
    *Connector not snugly plugged in
  • Garbled Windows display
    *Bad video driver
    *Correct problem in Safe Mode
  • Vertical stripes on Windows display
    *Corrupted video driver
    *Physical defect in video card
    *Not the monitor’s fault
  • Windows won’t start except in safe mode
    *Bad Windows video driver
    *Wrong driver installed for video card
  • Pictures and colors look bad
    *Too low a color depth being used
    *Video card not recognized, so it is using standard VGA mode (16 color)
    *Install driver for exact model of video card
  • Certain Applications Crash
    *Video driver not up-to-date
    *Patch for application required
    *New version of DirectX required